{"id":"CVE-2021-41836","aliases":["EUVD-2021-28837","GHSA-4rfr-wr94-r2xv"],"status":"published","title":"Fathom Analytics \u003c= 3.0.4 Authenticated Stored Cross-Site Scripting","description":"The Fathom Analytics WordPress plugin is vulnerable to Stored Cross-Site Scripting due to insufficient input validation and escaping via the $site_id parameter found in the ~/fathom-analytics.php file which allowed attackers with administrative user access to inject arbitrary web scripts, in versions up to and including 3.0.4. This affects multi-site installations where unfiltered_html is disabled for administrators, and sites where unfiltered_html is disabled.","severity":{"version":"3.1","score":4.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00583,"percentile":0.48226,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-79"],"published":"2021-12-14T15:50:10Z","modified":"2026-06-17T04:08:59Z","products":[{"vendor":"conva","product":"fathom_analytics"},{"vendor":"fathom analytics","product":"fathom analytics"}],"references":[{"url":"https://www.wordfence.com/vulnerability-advisories/#CVE-2021-41836","tags":["x_refsource_MISC","x_transferred","Third Party Advisory"]},{"url":"https://plugins.trac.wordpress.org/changeset?sfp_email=\u0026sfph_mail=\u0026reponame=\u0026old=2641005%40fathom-analytics\u0026new=2641005%40fathom-analytics\u0026sfp_email=\u0026sfph_mail=","tags":["x_refsource_MISC","x_transferred","Patch","Third Party Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-41836"},{"url":"https://github.com/advisories/GHSA-4rfr-wr94-r2xv"}],"sources":{"cve":[{"id":"CVE-2021-41836","title":"Fathom Analytics \u003c= 3.0.4 Authenticated Stored Cross-Site Scripting","description":"The Fathom Analytics WordPress plugin is vulnerable to Stored Cross-Site Scripting due to insufficient input validation and escaping via the $site_id parameter found in the ~/fathom-analytics.php file which allowed attackers with administrative user access to inject arbitrary web scripts, in versions up to and including 3.0.4. This affects multi-site installations where unfiltered_html is disabled for administrators, and sites where unfiltered_html is disabled.","status":"published","published":"2021-12-14T15:50:10.933Z","modified":"2025-02-10T14:55:13.698Z","cvss":[{"version":"3.1","score":4.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T14:32:59.105382Z"}],"euvd":[{"id":"EUVD-2021-28837","description":"The Fathom Analytics WordPress plugin is vulnerable to Stored Cross-Site Scripting due to insufficient input validation and escaping via the $site_id parameter found in the ~/fathom-analytics.php file which allowed attackers with administrative user access to inject arbitrary web scripts, in versions up to and including 3.0.4. This affects multi-site installations where unfiltered_html is disabled for administrators, and sites where unfiltered_html is disabled.","status":"published","published":"2021-12-14T15:50:10Z","modified":"2025-02-10T14:55:13Z","cvss":[{"version":"3.1","score":4.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N","level":"medium"}],"updated_at":"2026-11-03T00:04:01.319038Z"}],"ghsa":[{"id":"GHSA-4rfr-wr94-r2xv","title":"The Fathom Analytics WordPress plugin is vulnerable to Stored Cross-Site Scripting due to...","description":"The Fathom Analytics WordPress plugin is vulnerable to Stored Cross-Site Scripting due to insufficient input validation and escaping via the $site_id parameter found in the ~/fathom-analytics.php file which allowed attackers with administrative user access to inject arbitrary web scripts, in versions up to and including 3.0.4. This affects multi-site installations where unfiltered_html is disabled for administrators, and sites where unfiltered_html is disabled.","status":"published","published":"2021-12-15T00:00:44Z","modified":"2023-02-01T05:07:03Z","cwes":["CWE-79"],"updated_at":"2026-11-02T14:50:28.399252Z"}],"nvd":[{"id":"CVE-2021-41836","description":"The Fathom Analytics WordPress plugin is vulnerable to Stored Cross-Site Scripting due to insufficient input validation and escaping via the $site_id parameter found in the ~/fathom-analytics.php file which allowed attackers with administrative user access to inject arbitrary web scripts, in versions up to and including 3.0.4. This affects multi-site installations where unfiltered_html is disabled for administrators, and sites where unfiltered_html is disabled.","status":"published","published":"2021-12-14T16:15:09.147Z","modified":"2026-06-17T04:08:59.457Z","cvss":[{"version":"3.1","score":4.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"secondary"},{"version":"2.0","score":3.5,"vector":"AV:N/AC:M/Au:S/C:N/I:P/A:N","level":"low","assessor":"primary"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T14:07:02.189991Z"}]}}